In related art, as a solid-state image pickup apparatus mounted on an image pickup apparatus such as a digital camera, a CIS is widely used. In a general CIS, pixel exposure and reading are performed on a row-by-row basis, so when an image of a subject moving quickly is taken, so-called focal plane distortion occurs.
In view of this, as a countermeasure against the occurrence of the focal plane distortion, a CIS equipped with a global shutter function capable of performing the pixel exposure and reading simultaneously for all pixels has been proposed (see, for example, Patent Literature 1).
FIG. 1 is a plan view showing an example of a basic structure in each unit pixel of a front-surface irradiation type CIS equipped with the global shutter function. FIG. 2 is a cross-sectional view corresponding to FIG. 1.
The unit pixel of a CIS 10 is formed of an HAD (Hole Accumulated Diode) structure, for example, and is provided with a photodiode (hereinafter, abbreviated to PD (the same holds true for the other components)) 11 that performs photoelectric conversion and a floating diffusion region (FD) 13 connected to the PD 11 via a transfer gate (TG) 12.
Further, in the unit pixel, via a overflow gate (OFG) 14, a charge drain region (overflow drain (OFD)) 15 connected to a constant voltage source VDD for resetting the PD 11 is disposed horizontally with respect to the PD 11.
The unit pixel is further provided with a reset transistor (RST), a select transistor (SEL), and an amplifier transistor (AMP) (not shown).
FD 13 holds charges generated in the PD 11, with the result that the global shutter function is achieved. It should be noted that, instead of the FD 13, a charge holding region that holds the charges generated in the PD 11 may be provided in some cases.